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Titan, with its thick, nitrogen-dominated atmosphere, has been seen from satellite and terrestrial observations to harbour methane clouds. To investigate whether atmospheric features such as clouds could also be visible from the surface of Titan, data taken with the Side Looking Imager (SLI) on-board the Huygens probe after landing have been analysed to identify any potential atmospheric features...
Asteroid 4 Vesta is the only currently identified asteroid for which we possess samples in the form of meteorites. These meteorites revealed us that Vesta is a differentiated body and that its differentiation produced a relatively thin basaltic crust that survived intact over its entire collisional history. The survival of the vestan basaltic crust has long been identified as a pivotal constraint...
In support of atmospheric remote sensing of Titan and jovian planets, we measured absorption cross sections of benzene (C6H6) in the 7–15µm region at temperatures between 235K and 297K. For this, high-resolution laboratory spectra of C6H6 were obtained using two cold cells (80cm and 2.07cm path length) configured to a high resolution Fourier-transform infrared (FT-IR) spectrometer, Bruker IFS-125HR,...
Recent modeling studies of the early Mars climate predict a predominantly cold climate, characterized by the formation of regional ice sheets across the highland areas of Mars. Formation of the predicted “icy highlands” ice sheets is coincident with a peak in the volcanic flux of Mars involving the emplacement of the Late Noachian – Early Hesperian ridged plains unit. We explore the relationship between...
Most sulfate minerals form only in specific pH conditions, making them useful markers of past environmental conditions on Mars. However, interpreting past environments requires a full understanding of the suite of minerals present, a task which is complicated by the fact that some minerals can spectrally mask others in the visible- to near-infrared (VNIR, 0.4–2.5μm). Here, we report VNIR spectra of...
Ancient layers of impact spherules provide a record of Earth's early bombardment history. Here, we compare different bombardment histories to the spherule layer record and show that 3.2–3.5Ga the flux of large impactors (10–100km in diameter) was likely 20–40 times higher than today. The E-belt model of early Solar System dynamics suggests that an increased impactor flux during the Archean is the...
Themis Regio is interpreted to be a hotspot rise underlain by one or more mantle plumes. Many volcanic features in the Themis region have high emissivity anomalies in Venus Express Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) data. Other high emissivity anomalies have been found to correspond to volcanic flows interpreted to be relatively recent (Smrekar et al. [2010a] Science 328, 605–608)...
Using visible and near infrared data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), we identified a sequence of hydrated sulfates and Fe/Mg-smectites in southwest Melas Chasma. Specifically, these hydrated sulfate and semectite deposits are interbedded and have been highly deformed. Equilibrium thermodynamic calculations of coupled basalt weathering and fluid evaporation predict...
Due to the high absorption of solar wind plasma on the lunar dayside, a large scale wake structure is formed downstream of the Moon. However, recent in-situ observations have revealed the presence of protons in the near-lunar wake (100 km to 200 km from the surface). The solar wind, either directly or after interaction with the lunar surface (including magnetic anomalies), is the source of these protons...
The results of our new photometric observations of the main-belt asteroid 4332 Milton are presented. These observations were obtained on two successive nights in August 2012 at Çanakkale University Observatory. The bimodal light curve amplitude and period were determined to be 0.16 ± 0.01 mag and 3.295 ± 0.005 h, respectively.
Detailed chemical, structural and spectroscopic properties of jarosite solid solution minerals are key information for their potential discoveries by future remote sensing and in-situ detections on Mars. We successfully synthesized seven homogeneous K–Na jarosite solid solutions under hydrothermal conditions at 140°C, whose phase identifications and chemical compositions are confirmed by X-ray diffraction...
A physically-realistic migrating vortex model is developed and applied to generate pressure and wind speed and direction histories for dust devil passage. The asymmetric character of wind histories is noted, and we examine how these combined data constrain the solution space of dust devil parameters (migration velocity, diameter and intensity), ambient wind, and miss distance. These histories are...
Investigations of the variability, structure and energetics of the m=1−3 traveling waves in the northern hemisphere of Mars are conducted with the MarsWRF general circulation model. Using a simple, annually repeatable dust scenario, the model reproduces many general characteristics of the observed traveling waves. The simulated m=1 and m=3 traveling waves show large differences in terms of their structures...
Based on spectroscopic and photometric observations we analyzed the dust environment of two minor distant objects, P/2008 CL94 (Lemmon) and P/2011 S1 (Gibbs). Both targets demonstrated the comet-like activity beyond the “zone of water–ice sublimation”. Meanwhile the spectrum of P/2008 CL94 (Lemmon) did not reveal molecular emission features above reflected continuum in a spectral region of 4100–6800Å...
Ion chemistry appears to be deeply involved in the formation of heavy molecules in the upper atmosphere of Titan. These large species form the seeds of the organic aerosols responsible for the opaque haze surrounding the biggest satellite of Saturn. The chemical pathways involving individual anions remain however mostly unknown. The determination of the rates of the elementary reactions with ions...
The region of Titan’s hydrocarbon sea, Ligeia Mare, where transient bright features were previously discovered, was anomalously bright in the first of two more recent Cassini RADAR observations but not the second. Another transient bright feature in a different region of Ligeia Mare was also discovered in the first of the new observations. Here we present all the high-resolution observations of the...
New observations of Neptune’s clouds in the near infrared were acquired in October 2013 with SINFONI on ESO’s Very Large Telescope (VLT) in Chile. SINFONI is an Integral Field Unit spectrometer returning a 64 × 64 pixel image with 2048 wavelengths. Image cubes in the J-band (1.09–1.41 µm) and H-band (1.43–1.87 µm) were obtained at spatial resolutions of 0.1″and 0.025″per pixel, while SINFONI’s adaptive...
The COSIMA mass spectrometer on board the ROSETTA orbiter has collected dust in the near coma of comet 67P/Churyumov-Gerasimenko since August 11, 2014. The collected dust particles are identified by taking images with a microscope (COSISCOPE) under grazing incidence illumination before and after exposure of the target to cometary dust. More than 10,000 dust particles >14 µm in size collected from...
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